Multifunctional Organic–Inorganic Hybrid Aerogel for Self‐Cleaning, Heat‐Insulating, and Highly Efficient Microwave Absorbing Material

TLDR

Multifunctionalization is the future direction for microwave absorbing materials, yet integrating multiple functions into a single material remains a major challenge. The study synthesizes an aerogel-type microwave absorber with multidimensional organic and inorganic components to pave the way for next‑generation multifunctional microwave absorbing materials. The aerogel is built from a 3D framework of polyacrylonitrile fibers and polybenzoxazine membranes, with carbon nanotubes forming an electrically conductive network and Fe₃O₄ nanoparticles uniformly dispersed. The aerogel exhibits an ultralight, ultrathin (1.5 mm) structure with a reflection loss of −59.85 dB, outperforms similar magnetic–dielectric hybrids, and also offers strong hydrophobicity, thermal insulation, self‑cleaning, infrared stealth, and heat‑insulating properties due to its cellular structure and synergistic organic–inorganic nanomaterials.

Abstract

Abstract Multifunctionalization is the future development direction for microwave absorbing materials, but has not yet been explored. The effective integration of multiple functions into one material remains a huge challenge. Herein, an aerogel‐type microwave absorber assembled with multidimensional organic and inorganic components is synthesized. Polyacrylonitrile fibers and polybenzoxazine membranes work as the skeleton and crosslinker, respectively, forming a 3D framework, in which carbon nanotubes are interconnected into an electrically conductive network, and Fe 3 O 4 nanoparticles are uniformly dispersed throughout the aerogel. Remarkably, the microwave absorption performances of the aerogel achieve ultralight, ultrathin (1.5 mm), and strong absorption (reflection loss of −59.85 dB) features. In particular, its specific reflection loss values considerably outperform the current magnetic–dielectric hybrids with similar components. Moreover, the aerogel possesses strong hydrophobicity and good thermal insulation, endowing it attractive functions of self‐cleaning, infrared stealth, and heat insulation that is even comparable to commercial products. The excellent multifunction benefits from the cellular structure of aerogel, the assembly of multidimensional nanomaterials, and the synergistic effect of organic–inorganic components. This study paves the way for designing next‐generation microwave absorbing materials with great potential for multifunctional applications.